DESCRIPTION (Applicant's abstract verbatim): There is a need for non-invasive, user-friendly cerebral oxygenation monitoring during one of the most vulnerable stages of life, the neonatal period. Near-infrared spectroscopy (NIRS) is an optically based technique that can be used to non-invasively and continuously monitor brain oxygenation by determining relative changes in oxyhemoglobin (delta HbO2) and deoxyhemoglobin (delta Hb) and absolute cerebral oxygen saturation (CrSO2). The summation of deltaHbO2 and delta Hb give changes in total hemoglobin (delta TotalHb). NIRS is based upon the use of the modified Beer-Lambert Law to distinguish between deltaHbO2 and delta Hb. By using low power laser diodes to effect the determination of the Beer-Lambert parameters, it will be possible to construct a small, relatively inexpensive NIRS device. This device will find great utility in neonatal centers and holds the promise of applications in other clinical situations where the degree of tissue oxygenation is desired. The primary objectives of this Phase II SBIR proposal are 1 ) to develop a low cost NIRS system to monitor delta Hb, delta HbO2, delta TotalHb, and CrSO2, specifically directed to neonatal monitoring, 2) to prove the clinical utility of NIRS in a neonatal ICU, and 3) to verify the NIRS parameters against blood samples drawn from the internal jugular vein of the neonate. PROPOSED COMMERCIAL APPLICATION: An instrument that can non-invasively and continuously monitor brain oxygenation changes of the neonate would be a valuable addition to every neonatal intensive care unit or medical facility. In 1995, there were ~3.9 million live births in the U.S. Of that, 0.76% of the infants died in the first year [27]. An analysis of the cause of death shows that ~74% (21,750infants) could have benefited from cerebral oxygenation monitoring. Low birth weight (<2,500g) is a risk factor associated with poor outcome [24]. In 1995, there were ~286,000 live low birth weight infants, with a mortality rate of 6.5% in the first year [27]. NIRS offers improved capability in neonatal monitoring to assist physicians in the care of several hundred thousand neonates and infants a year.